Thor Mining (LSE:THR) was trading 8.3pc higher at 0.26p on Friday morning after announcing a ‘key milestone’ at its part-owned Kapunda copper project in South Australia.
The firm revealed that a government-funded test work programme has now begun at the asset, in which EnviroCopper has entered a two-stage agreement to earn a 75pc stake. Thor holds a 25pc stake in EnviroCopper that can be increased to 30pc.
The work will see EnviroCopper drill numerous holes into the south portion of the Kapunda resource to assess the hydraulic properties of its host rock. Specifically, the firm will look for flow rates, effective porosity and permeability, and hydraulic connectivity. It will assay drill samples for both copper and gold, as well as other elements.
Thor’s executive chairman Mick Billing said the work represents a ‘key milestone’ in EnviroCopper’s work to demonstrate the technical viability of the in-situ recovery (ISR) process at Kapunda.
Unlike conventional mining operations, ISR centres around a chemical process called ‘leaching’, that – in layman’s terms – involves dissolving minerals underground in a solution before extracting them at the surface. As ISR is much cheaper and quicker than actually building a copper mine, EnviroCopper believes that the technique can bring lower-grade projects into economic territory.
Although it is well established in phosphate and uranium mining, ISR’s introduction to the copper sector has been relatively recent. Indeed, as it stands, two of the only examples of the method’s application in this way are the Gunnison and Florence copper projects in Arizona, operated by Excelsior Mining and Taseko respectively. However, EnviroCopper sees a bright future for the technique and plans to spearhead its growth.
‘We look forward to both the technical component of testing the hydraulic properties of the host rock, and also the drill sample assays, particularly for copper and gold,’ added Billing. ‘The Thor investment in EnviroCopper Limited is becoming one of increasing importance as the resource base at both Kapunda and Moonta grows, technical hurdles are addressed, and prospects for commercial viability continue to develop.’
As Billing mentions, EnviroCopper will move on to Moonta – its second 75pc-held project – once progress has been made at Kapunda. Moonta is located around 160km north-east of Adelaide within the historical copper triangle of South Australia, where around 300,000ts of copper were mined and processed between the 1860s and 1920s. Although it is an earlier-stage project than Kapunda, Moonta is also thought to be a much larger opportunity.
In August 2019, EnviroCopper announced an initial inferred resource estimate for the asset of 66.1MMts grading 0.17pc copper. This translates to 114,000ts of contained copper considered amenable to ISR, taking EnviroCopper’s business-wide managed resource inventory to 233,000ts.
However, this initial figure was formed from the analysis of just 164 drill holes at Moonta. This led to the identification of three copper deposits, called Wombat, Bruce, and Larwood. A further 308 holes already drilled over these deposits will feature in future resource modelling once quality assurance has been completed, providing an obvious opportunity for upside.
What’s more, all three deposits remain open along strike or at depth – providing EnviroCopper with a chance to identify mineralisation beyond that already discovered.
If EnviroCopper can prove ISR’s operational viability in the copper arena, then it hopes to introduce the technique at projects far beyond Kapunda and Moonta. Indeed, the firm has said that it aims to develop an expanded portfolio of opportunities, initially focusing solely on South Australia but potentially moving into other territories in the future. The company has also said it plans to list on a recognised exchange, potential providing interested market participants with a way of getting exposure beyond a Thor investment in the future.
To read our sister site MiningMaven’s recent, in-depth report on EnviroCopper and its plans, please click here.